MiR-122调控肝癌遗传印记基因PEG10的实验研究  

MIR-122 regulates the expression of PEG10 in hepatoma cell lines

作　　者：常莹[1] 何星星[1] 黎培员[1] 林菊生[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院肝病研究所,武汉430030

出　　处：《中华肝脏病杂志》2010年第4期288-291,共4页Chinese Journal of Hepatology

基　　金：国家自然科学基金（30471983,30872237）;国家重点基础研究发展计划（973计划,2007CB512900）

摘　　要：目的探讨遗传印记基因PEG10功能的异常与miRNA失调控的相关性。方法通过生物信息学网站TargetScan预测可能参与PEG10调控的miRNA分子，筛选到miR～122。通过基于taqman探针的实时定量逆转录聚合酶链反应，比较miR-122在原代正常肝细胞和3株肝癌细胞株（Huh7，Hep3B，HepG2）中的表达差异。将miR-122的分子前体转染HepG2细胞，观察转染前后PEG10在mRNA和蛋白水平的表达变化。多组均数间比较采用秩和检验，配对样本组间差异比较采用t检验。结果生物信息学预测结果显示，miR-122可能参与了PEG10的调控。实时定量逆转录聚合酶链反应结果显示，PHHC，Huh7、HepG2、Hep3B细胞miR-122的表达量（2^△ △ Ct值）分别为1．0578±0．0975、0．5600±0．0632、0．0068±0．0012、0．0058±0．0008，H=9．667，P〈0．05。与原代正常肝细胞相比，miR-122在肝癌细胞株中表现为完全（Hep3B、HepG2细胞）或部分缺失（Huh7细胞），其表达水平与PEG10呈负相关。将miR-122分子前体转入HepG2细胞后，PEG10在mRNA水平并未显示出明显的下调，但Western blot结果提示miR-122分子前体明显抑制了PEG10蛋白的表达。结论miR-122参与了遗传印记基因PEG10的调控，其调控主要发生在翻译阶段，即蛋白质水平。miRNA的失调控与肝癌的发生密切相关，其功能的异常可能早于受其调控的癌基因或抑癌基因的改变，是肝癌发生的早期事件，这为肝癌的早期预警和基因治疗提供了新思路。Objective Our previous work indicated that oeverexpresssion of imprinting gene PEG 10 is associated with malignant phenotype of hepatocellular carcinoma. The aim of this study is to explore whether disregulation of PEG10 leads to dysregulation of microRNAs. Methods In silico analysis using TargetScan indicated that miR-122 could regulate the expression of PEG10. The expression of miR-122 in three hepatoma cell lines, Huh7, Hep3B and HepG2 and in primary human normal liver cell were compared using real time RT-PCR. After pre-miR-122 was transfected into HepG2 cell, the levels of PEG 10 mRNA and protein were measured. Results In silico analysis revealed that miR-122 could regulate the expression of PEG 10. Real time RT-PCR indicated that miR-122 was not expressed in Hep3B and HepG2 cells, and only weakly expressed in Huh7 cells, but highly expressed in primary human normal liver ceils. The expression of miR-122 was negatively correlated with the expression of PEG10. After pre-miR122 was transfected into HepG2, the mRNA level of PEG10 was not increased, whereas the protein level of PEG 10 was increased. Conclusion miR-122 may be involved in regulation of PEG10 expression.

关 键 词：癌 肝细胞 基因疗法 MIRNA 遗传印记基因PEG10 

分 类 号：R735.7[医药卫生—肿瘤]